Faction Replacements:
The Athenian Empire - Replaces the Swadians;
The State of Lacedaemon (Spartans) - Replaces the Rhodoks;
The Boeotian League - Replaces the Vaegirs;
The Scythian Tribes - Replaces the Khergits;
The Thracian Tribes - Replaces the Nords;
New Systems:
Death Scripts - Everyone can die. Having a party with high surgery, wound treatment and first aid skills helps diminishing the risk. (Script adapted from MAW's "Death Script")
Lords' death - If they are captured, lords can also be killed, but expect several consequences. (Script adapted from Mirathei's "Gunthunder Script")
Assassination - The higher the number of enemies and lords killed, the higher the chance of being ambushed by skilled assassins. If they succeed, the character will be dead for good. It is possible, however, to recruit up to five bodyguard mercenaries that will stay with him at all times.
Ability to start your own kingdom and recruit your own lords (accessible through the camp menu) - Courtesy of Highlander
Sabotage - Once a kingdom has a low enough relation towards you, it is possible to pay spies to enter a town or castle to try and sabotage their food supplies. If they succeed, starvation will eventually force the enemy into surrender, provided the siege isn't lifted.
Formations - Courtesy of Mirathei (the keys are the same, please refer to this thread for further information.
Shield Bashing - Courtesy of Mirathei (hold defense then press attack to bash)
Gameplay Changes (list will be updated):
Horses are extremely expensive, due to their seldom appearance in our timeframe. Their charge has been increased and their hitpoints reduced.
Spears are faster, meaner and they usually hit three or four at a time, thanks to Mirathei's formation script. Good timing is the rule of thumb in a phalanx.
There are rare items to be looted, like spartan shields that can't be purchased. There are also unique items such as kings' shields or personal equipment, that may be sold for a good amount of gold or kept for personal use.
Increased party size and boosted leadership bonus to keep up with it.
Armies are stronger, and recruit units are not fielded anymore.
New Kingdom units (to be listed soon)
New Mercenary units (to be listed soon)